Brake apparatus



`Jim 18, 1940.` RQAAVERY f `l `2,204,120

BRAKE APPARATUS z I Filed Harsh 2:5, 19:59 2 sheets-sheer 2 /771lg// /nn /f/ I HIM A,

Inventor 52m/Myer A ttorneys Patented June 18, '1940 UNITED STATES PATENT OFFICE 2 Claims.

This invention appertains to new and useful improvements in combined fluid and mechanical brakes.

The principal object of the present invention is to provide a fool-proof structure consisting of the combination of fluid and mechanicalbrakes and wherein, in the event, the fluid brakes fail, the mechanical brakes will take eil'ect immediately.

n l0 other objects and advantages ofthe invention will become apparent to the reader of the following specification.

In the drawings: Y Figure, 1 represents a diagrammatic view showing the parts of the apparatus.

Figure 2 is a top plan view of the master and auxiliary cylinders and associated adjuncts.

Figure 3 is a section on the line 3 2 of Figure 2. Figure 4 is asection on the line 4-4'of Figure 1. Figure 5 is a section on the line 5'-5'of Figure 1. lkiigure 6 is a perspective view of the bellcrank yo e. v 1

Referring to'the drawings wherein like numerals designatelike parts, it can be seen that the numeral I represents the master cylinder. while numeral 6 represents l the auxiliary cylinder.V These cylinders can be mounted on suitable sup.

ports and the master cylinder i is o1' the usual construction having the connectingrod 'i extending into the same from the brake pedal 8, for operating they-usual piston means in said master cylinder 5.

As shown` in Figure 3. the auxiliary cylinder i has the piston 9^ operative therein' and from the head portion thereof extends the rod Il. This rod extends through the head II of the cylinder and connects by way of the pin and slot connection I2 to the lower end of the bellcrank I3 -which is tulcrumed as at I4. 'I'he upper end of the-bellcrank has the fork I S which straddles the mechanical brake control rod I6. A coiled tension spring -I'I has one end attached to the forward end of the rod Il at its opposite end to the rear end of the auxiliary cylinder 6. The forward end portion of the rod I6 has an offset therein defining the shoulder Il which is engageable with the 'pin I9 projecting' laterally from the pedal l and which is normally disposed in the path of the shoulder IB when the brakes' are in inoperative position.

The fluid supply line 2l extends from the master cylinder 5 tq the fluid brakes and from this line 2B extends the branchpipe 2| to the auxiliary cylinder 6. This cylinder 6 has the filler l5 plug 22. 4

(Cl. 18S- 106) It can now be seen that when the pedal is depressed to operate the iluid brakes, the fluid will be under pressure in the line 20 and also in the branch pipe 2l and the piston 9 in the auxiliary cylinder 6 will be moved rearwardly so as to B roclg the bellcrank i3 and result in the immediate lifting of the forward portion of the rod I6 so. that the shoulder Il will not be in the path of the pin I9.

However, in the event that thefiuid line fails 10 and there is no pressure on the auxiliary piston 9 (see Figure 3), the mechanical brakes operating rod i6 will remain lowered with the shoulder I8 in the path of the pin I9, so that the pin I9 opcrates against the shoulder I8 and results in the l5 operation of the mechanical brakes (not shown).

The link 23 from the rod I6 to the switch handle 24 is adapted to operate the switch generally referred to by numeral 25 when the rod is shifted to operate the mechanical brakes and this 20 switches in the circuit 26 with the signal or indicator 21 which makes available to the driver of the vehicle a notice that his mechanical brakes are operating instead of his fluid brakes.

While the foregoing specification sets forth the 25 invention in specific terms, it is to be understood that numerous changes in the shape, size and materials may be resorted to without departing from the spirit Aand scope of the invention as claimed hereinafter. 30

Having described the invention, what is claimed as new is: l

l. In combinationv with a iluid brake system including a master cylinderhaving a brakes attached iluid line extending therefrom, an aux- 35 iliarycylinder. a branch line from the brakes attached -iluid line to the auxiliary cylinder,

Amechanical lbrakes. a control member for the mechanical brakes having an abutment thereon,

a foot pedal for operating the master cylinder, 40 said foot pedal having a laterally disposed projection normally in the path of the abutment, 4 said auxiliary cylinder being provided with a piston therein. and means between the piston and the mechanical brakes controlling member 45 whereby the latter is moved to a position with its abutment out of the pathv of' the laterally disposed member on the foot pedal when the piston of the auxiliary cylinder is under pressure of the iluid connections to the brakes, said means 50 between the piston and the mechanical brakes controlling member comprising a. bellcrank connected at one end to the piston and being engaged at its opposite end with the mechanical brakes controlling member.

2. m combination with s nula brake miem mciuding a master cylinder having a brake attached fluid line extending therefrom, an auxillary cylinder, a brachline from the brake attached iluid line to the auxiliary cylinder. mechanical brakes, a, controlled member for the mechanical brakes, said control member consisting-.oi an elongated longitudinal rod having an oil'set at lts intermediate portion denning a. shoulder. a foot pedal having a laterally disposed projection.` normally in the path oi the abutment.

said auxiliary cylinder being provided with a piston therein, means between the piston and the mechanical brake controlling member. :whereby the path of *he prolection.

no4-,vso l f the latter'is moved to a position with its shoulder out oi the path o f the projection on the foot pedal when the piston of the auxiliary cylinder is under pressure of the uidJine to ,the brakes, said means between the piston and the mechanical brake controlling member comprising a beilerank connected at one end to thle'piston and being engaged at its opposite end with the mechanical brake controlling member and a tensioned spring for` holding the mechanical ,brake controlling member urged into ,position against the bell, crank and to maintain the shoulder in` Rumi A. AVERY. 

